(A ∪ B) ‘ = A’ ∩ B’ and (A ∩ B) ‘= A’∪ B’ is known as / » Mathematical Tools for Economics 1 solved MCQs / By admin Question: (A ∪ B) ‘ = A’ ∩ B’ and (A ∩ B) ‘= A’∪ B’ is known as A. de morgan’s law B. distributive law C. associative law D. commutative law Answer» a. de morgan’s law Note: The above multiple-choice question is for all general and Competitive Exams in India.